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Identification of the phosphatidylserine (PS) discrepancies occurring on the cellular membrane during apoptotic processes is of the utmost importance. However, monitoring the quantity of PS molecules in real-time at a single-cell level currently remains a challenging task. Here, we demonstrate this objective by leveraging the specific binding and reversible interaction exhibited by the zinc(II) dipyridinamine complex (ZnDPA) with PS. Lipoic acid-functionalized ZnDPA (LP-ZnDPA) was subsequently immobilized onto the surface of an atomic force microscopy cantilever to form a force probe, ALP-ZnDPA, enabling a PS-specific dynamic imaging and detection mode. By utilizing this technique, we can not only create a heat map of the expression level of PS with submicron resolution but also quantify the number of molecules present on a single cell's surface with a detection limit of 1.86 × 104 molecules. The feasibility of the proposed method is demonstrated through the analysis of PS expression levels in different cancer cell lines and at various stages of paclitaxel-induced apoptosis. This study represents the first application of a force probe to quantify PS molecules on the surface of individual cells, providing insight into dynamic changes in PS content during apoptosis at the molecular level and introducing a novel dimension to current detection methodologies.
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Fosfatidilserinas , Imagem Individual de Molécula , Fosfatidilserinas/química , Apoptose , Membrana Celular/metabolismo , Microscopia de Força Atômica/métodos , Análise EspectralRESUMO
Ginger is an important cooking spice and herb worldwide, and scientific research has gradually confirmed the effect of ginger on preventing hair loss. Cedrol (CE) is a small sesquiterpene molecule in ginger and its external administration (EA) has shown hope in promoting hair growth, and alternative administration mode has become a potential treatment scheme to improve the efficacy of CE. The purpose of this study is to evaluate the effects of oral administration (OA) and EA of CE on hair regeneration of C57BL/6 alopecia areata (AA) mice induced by cyclophosphamide (CP) and to clarify the potential hair growth mechanism of CE in AA model in vitro and in vivo. The results showed that CE-OA has a shorter hair-turning black time and faster hair growth rate, and can lessen hair follicle damage induced by CP and promote hair follicle cell proliferation. Its effect is superior to CE-EA. At the same time, CE can increase the cytokines IFN-γ, IL-2, and IL-7 in the serum of mice, and decrease the expression of adhesion factors ICAM-1 and ELAM-1, thus alleviating the immunosuppression induced by CP. Mechanism research shows that CE regulates the JAK3/STAT3 signaling pathway, activates the Wnt3α/ß-catenin germinal center, and ameliorates oxidative stress induced by CP, thus promoting the proliferation of hair follicle cells and reversing AA. These results provide a theoretical basis for understanding the anti-AA mechanism of CE-OA, indicating that CE can be used as raw material for developing oral hair growth drugs.
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A novel zwitterionic polymer grafted silica stationary phase, Sil-PZIC, was prepared by bonding poly(ethylene maleic anhydride) molecules on the surface of silica via multiple binding sites, followed by ammonolysis of maleic anhydride through a nucleophilic substitution reaction with ethylenediamine. The stationary phase was characterized by solid-state 13C nuclear magnetic resonance, zeta potential, and elemental analysis and the results show the successful encapsulation of zwitterionic polymer on the surface of silica. The chromatographic performance of Sil-PZIC was investigated by using nucleosides and nucleic bases as test analytes The variation of retention and separation performance of these model compounds were investigated by varying the chromatographic conditions such as the components of mobile phase, salt concentration, and pH. The results show that the retention of the Sil-PZIC phase was dominated by a hydrophilic partitioning mechanism accompanied by secondary interactions such as electrostatic and hydrogen bonding. In addition, saccharides and Amadori compounds were also well separated on the Sil-PZIC, indicating that the Sil-PZIC column has potential application for separation of the polar compound.
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[This retracts the article DOI: 10.3892/ol.2020.11687.].
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Malondialdehyde (MDA) has long been served as a crucial indicator for assessing cellular oxidative stress levels. In this study, we introduce a new approach to determine cellular MDA levels based on a methyl tert-butyl ether (MTBE) extraction, aimed at eliminating interferences from cellular components during thiobarbituric acid (TBA) derivatization of MDA. By leveraging the effective MTBE extraction, we identified that the determination of the MDA-TBA adduct formed from the MTBE extraction layer can effectively eliminate the interferences from cellular proteins and metabolites. This method demonstrated acceptable linearity and precision in cellular samples and showed significant differences in H2O2 treated cellular oxidative stress models. The MTBE extraction-based MDA-TBA approach provides a reliable, cost-effective, and feasible method to determine cellular MDA levels using batch microplate reader approach for the assessment of cellular oxidative stress.
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Peróxido de Hidrogênio , Malondialdeído , Éteres Metílicos , Estresse Oxidativo , Malondialdeído/metabolismo , Malondialdeído/análise , Estresse Oxidativo/efeitos dos fármacos , Éteres Metílicos/química , Humanos , Tiobarbitúricos/químicaRESUMO
2D nanomaterials, with extraordinary physical and chemical characteristics, have long been regarded as promising nanofillers in organic coatings for marine corrosion protection. The past decade has witnessed the high-speed progress of 2D nanomaterial-reinforced organic composite coatings, and plenty of breakthroughs have been achieved as yet. This review covers an in-depth and all-around outline of the up-to-date advances in 2D nanomaterial-modified organic coatings employed for the marine corrosion protection realm. Starting from a brief introduction to 2D nanomaterials, the preparation strategies and properties are illustrated. Subsequently, diverse protection models based on composite coatings for marine corrosion protection are also introduced, including physical barrier, self-healing, as well as cathodic protection, respectively. Furthermore, computational simulations and critical factors on the corrosion protection properties of composite coatings are clarified in detail. Finally, the remaining challenges and prospects for marine corrosion protection based on 2D nanomaterials reinforced organic coatings are highlighted.
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Objectives: Investigating the impact of cadmium (Cd) on annulus fibrosus (AF) cells and its potential mechanism was the purpose of the current study. Materials and Methods: Cd was cultivated in different concentrations (0, 1, 5, 10, and 20 µM) on AF cells and the potential effects of the metal were assessed. Using the CCK-8 method, cell viability and proliferation were identified. Using transcriptome analysis, the annulus fibrosus cells were sequenced both with and without cadmium chloride. The EdU method was used to determine the rate of cell proliferation; senescence-associated ß-galactosidase (SA-ß-Gal) staining was used to determine the number of positive cells; and western blot, RT-PCR, and immunofluorescence were used to determine the protein and mRNA expression of senescence-associated proteins (p16, p21, and p53) and c-Jun N-terminal kinase (JNK). Results: According to the findings, Cd has the ability to increase the production of senescence-associated genes (p16 and p21) and senescence-associated secreted phenotype (SASP), which includes IL-1ß and IL-6. Through the JNK/p53 signal pathway, Cd exposure simultaneously accelerated AF cell senescence and promoted SASP. Following JNK inhibitor (SP600125) treatment, the expression of p53, JNK, and senescence-associated indices were all down-regulated. Conclusion: By activating the JNK/p53 signaling pathway, Cd can induce oxidative stress damage and AF cell senescence. These findings could provide a new approach for treating and preventing intervertebral disc degeneration (IVDD) caused by Cd exposure.
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Snakebite envenomation often leads to severe visceral injuries, including acute liver injury (ALI). However, the toxicity mechanism remains unclear. Moreover, varespladib can directly inhibit phospholipase A2 (PLA2) in snake venom, but its protective effect on snakebite-induced ALI and the mechanism have not been clarified. Previous studies have shown that snake venom PLA2 leads to neuron cell death via reactive oxygen species (ROS), one of the initial factors related to the mitophagy pathway. The present study group also found that ROS accumulation occurred after Naja atra envenoming. Hematoxylin and eosin (H/E) staining and immunohistochemistry (IHC) were performed to identify the expression of inflammatory factors in the liver tissue, and flow cytometry and immunofluorescence were used to detect ROS levels and mitochondrial function. Immunofluorescence and western blotting were also used for detecting mitophagy pathway-related proteins. The results showed that N. atra bite induced ALI by activating mitophagy and inducing inflammation and that varespladib had a protective effect. Collectively, these results showed the pathological mechanism of ALI caused by N. atra bite and revealed the protective effect of varespladib.
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Acetatos , Indóis , Mitofagia , Fosfolipases A2 , Mordeduras de Serpentes , Animais , Camundongos , Mitofagia/efeitos dos fármacos , Fosfolipases A2/metabolismo , Mordeduras de Serpentes/tratamento farmacológico , Mordeduras de Serpentes/complicações , Cetoácidos/farmacologia , Masculino , Espécies Reativas de Oxigênio/metabolismo , Venenos Elapídicos/toxicidade , Fígado/efeitos dos fármacos , Fígado/patologia , Doença Hepática Induzida por Substâncias e DrogasRESUMO
Rechargeable magnesium battery is regarded as the promising candidate for the next generation of high-specific-energy storage systems. Nevertheless, issues related to severe Mg-Cl dissociation at the electrolyte-electrode interface impede the insertion of Mg2+ into most materials, leading to severe polarization and low utilization of Mg-storage electrodes. In this study, a metal-organic polymer (MOP) Ni-TABQ (Ni-coordinated tetramino-benzoquinone) with superior surface catalytic activity is proposed to achieve the high-capacity Mg-MOP battery. The layered Ni-TABQ cathode, featuring a unique 2D π-d linear conjugated structure, effectively reduces the dissociation energy of MgxCly clusters at the Janus interface, thereby facilitating Mg2+ insertion. Due to the high utilization of active sites, Ni-TABQ achieves high capacities of 410 mAh/g at 200 mA g-1, attributable to a four-electron redox process involving two redox centers, benzoid carbonyls, and imines. This research highlights the importance of surface electrochemical processes in rechargeable magnesium batteries and paves the way for future development in multivalent metal-ion batteries.
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CD47 is a ligand of SIRPα, an inhibitory receptor expressed by macrophages, dendritic cells, and natural killer (NK) cells, and, therefore, transgenic overexpression of CD47 is considered an effective approach to inhibiting transplant rejection. However, the detrimental effect of CD47 signaling is overlooked when exploring this approach. Here, we construct a mutant CD47 by replacing the transmembrane and intracellular domains with a membrane anchor (CD47-IgV). In both human and mouse cells, CD47-IgV is efficiently expressed on the cell surface and protects against phagocytosis in vitro and in vivo but does not induce cell death or inhibit angiogenesis. Furthermore, hematopoietic stem cells expressing transgenic CD47-IgV show no detectable alterations in engraftment or differentiation. This study provides a potentially effective means of achieving transgenic CD47 expression that may help to produce gene-edited pigs for xenotransplantation and hypoimmunogenic pluripotent stem cells for regenerative medicine.
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Angiogênese , Antígeno CD47 , Animais , Humanos , Camundongos , Antígeno CD47/genética , Antígeno CD47/metabolismo , Morte Celular , Fagocitose/genética , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , SuínosRESUMO
BACKGROUND: Recurrent aphthous stomatitis (RAS) is common in clinical practice and imposes both physical and psychological distress on patients. OBJECTIVE: This study aimed to evaluate the clinical effectiveness of fire needle therapy for the treatment of RAS, providing a basis for clinical decision-making. METHODS: Eight databases, in both Chinese and English, were searched from their inception until December 2022. All randomized controlled trials (RCTs) that utilized fire needle therapy, either alone or combined with other treatments for RAS, were considered. Data evaluation and extraction were conducted independently by 2 authors. RESULTS: The revised Cochrane Risk of Bias Version 2 tool was employed to assess the risk of bias in the included RCTs. A meta-analysis was conducted using Review Manager 5.4 and Stata 15.0. Nine RCTs involving 1469 patients were selected for inclusion. The meta-analysis revealed that, compared to a non-fire-needle control group (primarily utilizing vitamin and transfer factor treatments), fire needle therapy for RAS significantly improved the total effective rate (relative riskâ =â 1.25, 95% confidence interval [CI] [1.14, 1.36], Pâ <â .00001), reduced the visual analogue scale score (mean differenceâ =â -1.68, 95% CI [-1.82, -1.53], Pâ <â .0001), diminished the Traditional Chinese Medicine symptom score (standardized mean differenceâ =â -1.20, 95% CI [-1.76, -0.65], Pâ <â .0001), and shortened the healing time (mean differenceâ =â -1.66, 95% CI [-2.73, -0.59], Pâ =â .002). Notably, there was no significant difference in the recurrence rate between the groups (relative riskâ =â -0.18, 95% CI [-0.36, 0.01], Pâ =â .06). Further subgroup analysis on total efficacy rate was performed based on variables such as experimental group intervention, control group intervention, and duration of therapy to explore potential sources of heterogeneity. CONCLUSION: Fire needle therapy appears to be a clinically effective treatment for RAS, offering benefits such as pain alleviation, symptom improvement based on the Traditional Chinese Medicine parameters, and faster recovery. Nonetheless, the overall quality of the RCTs available raises concerns. Future research, involving high-quality RCTs, is essential to confirm the clinical efficacy and safety of this treatment. Registration number: PROSPERO (CRD42023387973).
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Estomatite Aftosa , Humanos , Medicina Tradicional Chinesa , Agulhas , Estomatite Aftosa/terapiaRESUMO
Incomplete recovery, baseline drift, and a long response time have been impeding the practical applications of transition metal dichalcogenide (TMD)-based gas sensors. Here, we report WS2 sensors with significantly improved gas recovery, rapid response, and negligible baseline drift by the incorporation of black phosphorus (BP) as well as the decoration of Pt to detect NO2 for the first time. Compared to bare WS2, the BP-WS2 sensors show higher sensitivity, better repeatability, and more excellent selectivity towards NO2 at the optimal operating temperature of 50 °C. Furthermore, the optimized 30%BP-WS2/Pt sensors exhibit a continuous enhancement in the recovery level and sensitivity with negligible baseline drift. The 30%BP-WS2/Pt sensor also exhibits a shorter response time of 28 s than 49.5 s for its counterpart WS2 sensor towards 32 ppm NO2. The enhanced sensing properties are primarily due to the combined effects of more adsorption sites provided by BP, the spill-over effect of Pt catalysis, and the WS2/BP heterostructure. Therefore, the Pt-decorated 30%BP-WS2 sensor exhibits prominent gas-sensing properties of high gas sensitivity, a low detection limit of 100 ppb, good selectivity, and fast response. Our strategy provides a new route for designing and optimizing TMD-based gas sensors with excellent gas-sensing performance.
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BACKGROUND: The development of efficent chromatographic stationary phases (SP) with mixed-mode or multiple interactions in high-performance liquid chromatography (HPLC) for the separation of complex samples is a challenging task. Metal organic frameworks (MOFs)-based SP can provide desired multiple interactions and enable the separation of a diverse range of solutes, but have limitations of low column efficiency and poor stability. RESULTS: Herein, the hybrid MOFs@Covalent organic frameworks (COFs) materials were used as SP in HPLC due to their synergistic structural features. The SiO2@NH2-UiO-66@CTF SP was synthesized by integration of NH2-UiO-66 and covalent triazine framework (CTF) onto silica surface. Due to the unique structure of SiO2@NH2-UiO-66@CTF with hierarchical-pores, this column showed higher column efficiency (up to 49,369 plates m-1 for alkylbenzenes) than the reported columns packed with MOFs-based SP. Owing to the Zr4+-N coordination bonding between CTF and NH2-UiO-66, the structural stability of SiO2@NH2-UiO-66@CTF can be improved. Furthermore, this new column exhibited remarkable column stability with relative standard deviation of retention time of <0.40% after 400 injections. With the combined advantages of multifunctional properties, high column efficiency, and good stability, SiO2@NH2-UiO-66@CTF SP showed excellent selectivity for the separation of a variety of hydrophobic, aromatic, heteroatomic, and hydrophilic analytes. SIGNIFICANCE AND NOVELTY: This work not only offers a promising SP with multiple retention mechanisms for HPLC, but also provides an efficient strategy for development of high column efficiency MOFs-based SP with good stability. Moreover, the MOFs@COFs hybrid materials were expanded in application area through this study, and the research results can also afford the foundation for further explore its structural characteristics.
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Sweat is an accessible biofluid that provides useful physiological information about the body's biomolecular state and systemic health. Wearable sensors possess various advantageous features, such as lightweight design, wireless connectivity, and compatibility with human skin, that make them suitable for continuous monitoring. Wearable electrochemical sweat sensors can diagnose diseases and monitor health conditions by detecting biomedical signal changes in sweat. This paper discusses the state-of-the-art research in the field of wearable sweat sensors and the materials used in their construction. It covers biomarkers present in sweat, sensing modalities, techniques for sweat collection, and ways to power these sensors. Innovative materials are categorized into three subcategories: sweat collection, sweat detection, and self-powering. These include substrates for sensor fabrication, analyte detection electrodes, absorbent patches, microfluidic devices, and self-powered devices. This paper concludes by forecasting future research trends and prospects in material-based wearable non-invasive sweat sensors.
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BACKGROUND: Aflatoxin B1 (AFB1) and its precursors contaminate food and agricultural products, posing a significant risk to food safety and human health, but simultaneous and effective extraction and determination of AFB1 and its precursors with varied structures is still a challenging task. RESULTS: In this study, a bisimidazolium-type ionic liquid functionalized mesoporous multipod silica (SiO2@mPMO-IL(im)2) was fabricated to extract AFB1 and its two precursors, i.e., averantin and sterigmatocystin. The SiO2@mPMO-IL(im)2 could simultaneously extract three targets with varied structures based on the multipods, mesopores, and multifunctional groups. The density functional theory calculations further verified the multiple interactions between SiO2@mPMO-IL(im)2 and targets. The fabricated SiO2@mPMO-IL(im)2 could effectively extract and determine three targets in grains by combing with dispersive solid-phase extraction and high-performance liquid chromatography. Good linearity (r2 > 0.9978), low LODs (0.9-1.5 µg kg-1) and LOQs (3.0-4.5 µg kg-1), satisfactory spiked recoveries (92.5%-106.8%) and high precisions (RSD<6.4%) were observed. SIGNIFICANCE AND NOVELTY: This work demonstrates the feasibility of SiO2@mPMO-IL(im)2 for simultaneous and effective extraction of toxins with varied structures and provides a promising sample preparation for the analysis of AFB1 and its precursors in grain samples.
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Aflatoxina B1 , Líquidos Iônicos , Humanos , Dióxido de Silício , Grão Comestível , AgriculturaRESUMO
Acinetobacter baumannii has developed multiple drug resistances, posing a significant threat to antibiotic efficacy. LysECD7, an endolysin derived from phages, could be a promising therapeutic agent against multi-drug resistance A. baumannii. In this study, in order to further enhance the antibacterial efficiency of the engineered LysECD7, a few lipopolysaccharide-interacting peptides (Li5, MSI594 and Li5-MSI) were genetically fused with LysECD7. Based on in vitro antibacterial activity, the fusion protein Lys-Li5-MSI was selected for further modifications aimed at extending its half-life. A cysteine residue was introduced into Lys-Li5-MSI through mutation (Lys-Li5-MSIV12C), followed by conjugation with a C16 fatty acid chain via a protonation substitution reaction(V12C-C16). The pharmacokinetic profile of V12C-C16 exhibited a more favorable characteristic in comparison to Lys-Li5-MSI, thereby resulting in enhanced therapeutic efficacy against lethal A. baumannii infection in mice. The study provides valuable insights for the development of novel endolysin therapeutics and proposes an alternative therapeutic strategy for combating A. baumannii infections.
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Infecções por Acinetobacter , Acinetobacter baumannii , Antibacterianos , Endopeptidases , Lipopolissacarídeos , Proteínas Recombinantes de Fusão , Animais , Feminino , Camundongos , Acinetobacter baumannii/efeitos dos fármacos , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Antibacterianos/farmacologia , Antibacterianos/química , Modelos Animais de Doenças , Endopeptidases/farmacologia , Endopeptidases/metabolismo , Endopeptidases/química , Endopeptidases/genética , Ácidos Graxos/metabolismo , Ácidos Graxos/química , Ácidos Graxos/farmacologia , Lipopolissacarídeos/metabolismo , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Peptídeos/farmacologia , Peptídeos/química , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/químicaRESUMO
Low mechanical strength is still the key question for collagen hydrogel consisting of nanofibrils as hard tissue repair scaffolds with no loss of biological function. In this work, novel collagen nanofibrous hydrogels with high mechanical strength were fabricated based on the pre-protection of trisodium citrate masked Zr(SO4)2 solution for collagen self-assembling nanofibrils and then further coordination with Zr(SO4)2 solution. The mature collagen nanofibrils with d-period were observed in Zr(IV) mediated collagen hydrogels by AFM when the Zr(IV) concentration was ≥ 10 mmol/L, and the distribution of zirconium element was uniform. Due to the coordination of Zr(IV) with âCOOH, âNH2 and âOH within collagen and the tighter entanglement of collagen nanofibrils, the elastic modulus and compressive strength of Zr(IV) mediated collagen nanofibrous hydrogel were 208.3 and 1103.0 kPa, which were approximate 77 and 12 times larger than those of pure collagen hydrogel, respectively. Moreover, the environmental stability such as thermostability, swelling ability and biodegradability got outstanding improvements and could be regulated by Zr(IV) concentration. Most importantly, the resultant hydrogel showed excellent biocompatibility and even accelerated cell proliferation.
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Proliferação de Células , Colágeno , Hidrogéis , Nanofibras , Zircônio , Hidrogéis/química , Zircônio/química , Nanofibras/química , Colágeno/química , Proliferação de Células/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Tamanho da Partícula , Força Compressiva , Propriedades de SuperfícieRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Sophora flavescens Ait.-Angelica sinensis(Oliv.) Diels drug pairing (SA) is a transformed drug pairing from Shengui pill, a traditional Chinese medicine prescription in the ninth volume of Traditional Chinese Medicine classic "Gu Jin Yi Jian", which is famous for clearing heat, moistening dryness, and promoting blood circulation. It is commonly used in the treatment of eczema, a skin condition that causes itching and inflammation. Despite its widespread use, there is still limited research on the mechanism of how SA treats eczema. This paper aims to fill this gap by conducting animal experiments to uncover the mechanism behind SA's therapeutic effects on eczema. Our findings provide a solid foundation for the clinical use of this TCM prescription. AIM OF THE STUDY: The basic purpose of this study is to clarify the therapeutic mechanism of Sophora flavescens-Angelica sinensis (SA) in the treatment and control of eczema. MATERIALS AND METHODS: The chemical compositions of SA were analyzed using HPLC-Q-Orbitrap-MS. In vivo, a mouse model of eczema was created, and the serum levels of TNF-α and IL-1ß were quantified using an enzyme-linked immunosorbent assay (ELISA). Hematoxylin and eosin (HE) staining was performed to assess the pathological state of the mouse skin, and immunohistochemical technique (IHC) was employed to estimate the contents of TNF-α, TLR4, and NF-κB semi-quantitatively. The expression levels of TLR4, MyD88, and NF-κB mRNA were determined through real-time quantitative polymerase chain reaction (qRT-PCR). Western Blotting was utilized to identify the protein levels of TLR4, MyD88, and NF-κB in mouse skin tissue. RESULTS: SA identified 18 active chemicals, some of which were shown in vivo to inhibit the TLR4/MyD88/NF-κB signaling pathway while reducing serum levels of TNF-α and IL-1ß, making them ideal agents for the treatment of eczema. CONCLUSIONS: SA's anti-inflammatory properties are attributed to its ability to reduce serum levels of TNF-α and IL-1ß, likewise inhibit the TLR4/MyD88/NF-κB signaling pathway.
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Angelica sinensis , Eczema , Camundongos , Animais , NF-kappa B/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Sophora flavescens , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Biochar shows great potential in soil cadmium pollution treatment, however, the effect and mechanisms of biochar on cadmium passivation (CP) during the long-term process of soil from flooding to natural air-drying are not clear. In this study, a 300-day experiment was conducted to keep the flooded water level constant for the first 100 days and then dried naturally. Mechanisms of CP by lignin biochar (LBC) were analyzed through chemical analysis, FTIR-2D-COS, EEMs-PARAFAC, ultraviolet spectroscopy characterizations, and microbial community distribution of soil. Results showed that application of LBC results in rapid CP ratio in soil within 35 days, mainly in the residual and Fe-Mn bound states (total 72.80%). CP ratio further increased to 90.89% with water evaporation. The CP mechanisms include precipitation, electrostatic effect, humus complexation, and microbial remediation by promoting the propagation of fungi such as Penicillium and Trichoderma. Evaporation of water promoted the colonization of aerobic microorganisms and then increased the degree of soil humification and aromatization, thereby enhancing the cadmium passivation. Simultaneously, the biochar could reduce the relative abundance of plant pathogens in soil from 1.8% to 0.03% and the freshness index (ß/α) from 0.64 to 0.16, favoring crop growth and promoting carbon sequestration and emission reduction.
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Cádmio , Carvão Vegetal , Lignina , Microbiologia do Solo , Poluentes do Solo , Carvão Vegetal/química , Cádmio/química , Poluentes do Solo/química , Lignina/química , Inundações , Solo/química , DessecaçãoRESUMO
Inhibiting the adhesion and growth of marine microorganisms through photocatalysis is a potentially efficient and environmentally friendly antifouling strategy. However, the undesired "shading effect" caused by resin coatings and microbial deposition reduces the utilization of the catalysts and leads to a failure in the antifouling active substance on the coating surface. Here, we successfully developed a composite coating (DPC-x) combining g-C3N4 nanosheet (g-C-NS) photocatalysts with degradable green poly-Schiff base resins, which integrates the dual functions of enhanced dynamic self-renewal and photocatalytic antibacterial activities towards long-term anti-biofouling. The controllable and complete degradability of the poly-Schiff base polymer chains and the self-renewal mechanism of the DPC-x coating exposed the internal g-C-NS, which provided a constant stream of photocatalytic reactive interfaces for 100% utilization and release of the photocatalysts. g-C-NS were homogeneously dispersed in the degradable resin coating, significantly enhancing and adjusting the self-renewal rate of the poly-Schiff base resin coating in visible light. The degradation reaction rate of DPC-0.2 (20 wt% g-C-NS) was 40 times that of DPC, thus improving the capabilities of surface self-renewal and fouling-release. Due to the synergistic antifouling mechanism of the efficient antibacterial properties and the enhanced degradation/self-renewal, the antimicrobial rates of DPC and DPC-0.2 were 94.58% and 99.31% in the dark, and 98.2% and 99.87% in visible light. DPC-x has excellent all-weather antimicrobial efficacy and could offer a new perspective on eco-friendly marine antifouling strategies.